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In the latest Solo update, we debuted an important new flight safety feature: Custom Geofencing. This is basically scene awareness through software, and it’s an innovative approach to the object avoidance problem that other companies are trying to solve with hardware alone. Here’s a look behind the technology, as well as our philosophy behind taking the software approach.


“Sense and avoid” technology is, like, so hot right now. At least the theory of sense-and-avoid (S&A) is. In short, by outfitting drones with special sensors (optical flow / sonar / LIDAR), the craft will be able to sense nearby objects and avoid flying into them. Obviously this is an important step for increased safety. This technology is currently available on high-end drones, and it works fairly well. What’s more, the size and the cost of those special sensors are just now trickling down to the point where it’s feasible to integrate them with consumer drones.

This spring, DJI released the Phantom 4, the first mass-marketed consumer drone to boast sense-and-avoid hardware. It’s certainly exciting to see this technology on a popular drone. And again, it’s great in theory, but the technology just isn’t quite good enough for us to put our brand behind it.

Unidirectional: The P4’s sensor is only forward-facing. This means it cannot detect objects to either side or behind. It might give first-time pilots a false sense of security, which we definitely want to avoid.

Coarse: The P4 sensor cannot detect smaller objects, such as power lines and tree branches. It can sense things like trees and walls and cliffs. And again, it can only sense these things if they’re directly in front of the drone. You know who else has an easy time seeing a building directly in front of their drone? You.

Not fully-functional: It won’t work in Sport mode, the more advanced, faster and risky flight mode to use; it goes to reason that this is the mode that operators would benefit most from S&A.

Not for pros: Considering the above, the P4’s S&A tech doesn’t have much if any benefit for the pro owner. (And it might instill beginners with a false sense of security and confidence.) Pros will probably not be flying headlong into cliffs (well, perhaps in Sport mode…), but they will often want to get close to objects that they’re shooting. If they do, the S&A kicks in and automatically sends the drone up, which could affect the shot.

Our solution: Interactive scene awareness

We decided to wait to incorporate these sensors until the hardware was up to our standards and those of our users. So instead of a hardware solution, we addressed the S&A problem with the innovation 3DR is proud of: in-app software.

We’ve incorporated custom geofencing into our latest Solo app release. (Note that this is not the kind of geofencing DJI incorporates, which blocks you from flying altogether in certain areas, such as national parks and a 30-mile radius around Washington, D.C.) The Solo app now gives you the ability to define an area around Solo that your drone will never leave. Think of it as setting up an invisible fence for your dog.

On your map view, you can enable or disable geofencing. When it’s on, you will have four points (like dropped pins) that you use to make a virtual quadrilateral flight cage around your drone. Solo uses GPS to set and obey this boundary. You can move your four points to change the shape, size and location of your quadrilateral at any time in flight, blocking off any objects or areas you choose. This also means that if you want to fly in another area, simply move your pins on your screen and you’ll create a new safe zone — or you can turn the geofence off altogether.

Why this is important

It works.

Safe: Because it’s a hard fence, it really does keep your drone away from objects, even power lines.

Customizable: If you don’t want that hard fence there, you can move it to where you want it, or easily disable or enable it.

Engaging: Perhaps the most important advantage. Instead of stopping you from thinking about the environment around you, like hardware sensors would do, geofencing keeps pilots engaged and aware. This level of interaction with your drone and with your environment is critical for any truly holistic approach to drone safety, as opposed to blindly trusting an imperfect technology.

Here’s wishing you happy and safer flying!